Retirement-Related Benefits - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2024 USD ($)
Pension Plan
Expected Benefit Payments
2025	$ 3,338
2026	3,282
2027	3,300
2028	3,243
2029	3,221
2030-2034	15,243
Other Postretirement Benefits Plan
Expected Benefit Payments
2025	272
2026	280
2027	293
2028	299
2029	293
2030-2034	1,350
United States \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2025	1,136
2026	1,178
2027	1,214
2028	1,202
2029	1,186
2030-2034	5,671
United States \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2025	121
2026	119
2027	116
2028	114
2029	111
2030-2034	507
United States \| Other Postretirement Benefits Plan
Expected Benefit Payments
2025	230
2026	237
2027	249
2028	253
2029	246
2030-2034	1,090
Non-U.S. Plans \| Pension Plan \| Qualified Plan
Expected Benefit Payments
2025	1,833
2026	1,760
2027	1,749
2028	1,710
2029	1,705
2030-2034	8,049
Non-U.S. Plans \| Pension Plan \| Nonqualified Plan
Expected Benefit Payments
2025	248
2026	224
2027	221
2028	217
2029	218
2030-2034	1,016
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Qualified Plan
Expected Benefit Payments
2025	16
2026	17
2027	18
2028	18
2029	19
2030-2034	107
Non-U.S. Plans \| Other Postretirement Benefits Plan \| Nonqualified Plan
Expected Benefit Payments
2025	26
2026	27
2027	27
2028	27
2029	28
2030-2034	$ 153

No definition available.

Name:	us-gaap_DefinedBenefitPlanEstimatedFutureBenefitPaymentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanTaxStatusAxis=us-gaap_QualifiedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanTaxStatusAxis=us-gaap_NonqualifiedPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=us-gaap_ForeignPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: